'''Hidden channels''' (covert channels) are communication channels that transmit information without the authorization or knowledge of the channel's designer, owner, or operator.

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== Tear Down ==

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== Common Uses ==

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<ol start="1">

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<li>Remove the back panel.</li>

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</ol>

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* Bypassing network filters;

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{| border="1" cellpadding="2"

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* Bypassing network [[Sniffer|sniffers]].

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| [[File:1-bb9320-BackPanelRemoved.jpg| 300px ]]

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== Techniques ==

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<ol start="2">

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<li>Remove the SIM and SD Memory Card.</li>

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</ol>

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Information can be hidden within:

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<ol start="3">

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<li>Using a torx-6 screw driver remove the 2 visible screws on the back of the phone.</li>

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</ol>

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* IP ID;

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{| border="1" cellpadding="2"

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* TCP ISN;

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* TCP options;

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| [[File:2-bb9320-ScrewRemoval.jpg| 300px ]]

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* DNS ID;

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* HTTP cookie;

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* etc.

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== Detection of hidden channels ==

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<ol start="4">

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<li>Remove the screen protector using a shim, guitar pick, or prying tool.</li>

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</ol>

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Generally, it is impossible to detect well-designed hidden channels by means of traffic analysis. For example, information hidden within TLS ''Client/Server Hello'' random bytes in encrypted form cannot be distinguished from bytes produced by secure random number generator.

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{| border="1" cellpadding="2"

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| [[File:3-bb9320-ScreenRemoval.jpg| 300px ]]

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However, it is possible to detect hidden channels by detecting attendant events, such as successful intrusion attempts. Some hidden channels produce network anomalies, for example, hidden channels using DNS ID to hide information may produce large number of DNS queries without further communication between hosts.

<li>Continue working under the high heat. With the 9315/9320's I've worked on the eMMC has been ready to lift off of the main board using tweezers immediately after removing the heat shield.</li>

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</ol>

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{| border="1" cellpadding="2"

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| [[File:14-bb9320-EMMC-Removed.jpg| 300px ]]

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<ol start="5">

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<li>Using liquid flux, or flux paste and a soldering iron clean the pads on the eMMC in preparation for a read</li>

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</ol>

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{| border="1" cellpadding="2"

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| [[File:15-bb9320-EMMC-Cleanup.jpg| 300px ]]

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| [[File:16-bb9320-EMMC-Clean.jpg| 300px ]]

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<ol start="6">

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<li>The eMMC is now ready to read using the appropriate adapter/programmer and software.</li>

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</ol>

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At the time of this writing (2013OCT29) the eMMC that was removed in this example was read using an UP828 programmer via the "VBGA169E" adapter. The resulting image was then parsed via the CelleBrite Physical Analyzer (V. 3.8.5.108).

Revision as of 17:26, 30 October 2013

Tear Down

Remove the back panel.

Remove the SIM and SD Memory Card.

Using a torx-6 screw driver remove the 2 visible screws on the back of the phone.

Remove the screen protector using a shim, guitar pick, or prying tool.

Remove 2 torx-5 screws.

Use the shim to detach the outer bezel/keyboard from the device.

5-1-bb9320-TopPlate.jpg| 300px ]]

Remove 4 additional torx-6 screws. The main board will now easily be separated from the back plate

Remove the final torx-4 screw located beneath the plastic protector, to remove the plastic keyboard overlay.

Disconnect the ribbon cable connected to the LCD. Then using a pick separate the display from the main board.

The tear down is now complete

eMMC Removal

The eMMC is located beneath the heat shield directly above the Micro SD card slot.

Place the main board in a stand or holder and position it approximately 2 1/2" - 3" inches away from a heat gun or device the blows super hot air.

Monitoring the temperature the heat shield will come off easily between 190-200 Centigrade.

13-bb9320-HeatShieldRemoved.jpg| 300px ]]

Continue working under the high heat. With the 9315/9320's I've worked on the eMMC has been ready to lift off of the main board using tweezers immediately after removing the heat shield.

Using liquid flux, or flux paste and a soldering iron clean the pads on the eMMC in preparation for a read

The eMMC is now ready to read using the appropriate adapter/programmer and software.

At the time of this writing (2013OCT29) the eMMC that was removed in this example was read using an UP828 programmer via the "VBGA169E" adapter. The resulting image was then parsed via the CelleBrite Physical Analyzer (V. 3.8.5.108).